How to rotate vertices ?

Im trying to achieve glass shatter effect, so far the only idea I can come up with is to randomly generate mesh plane with a lots of triangles, select 3-4-or more connected vertices in a group, move and rotate them away. My problem with this is that I can't see how possibly could I rotate group of vertices without involving heavy maths . Was expecting to be able to apply matrix but.. I hit the wall again.

Better if it can be done in the single mesh - then still only one object to draw.

Well not in gideros: lua is rather slow and modifying vertices means reuploading them to GPU. On the other hand gideros rendering pipeline is very close to the GPU, and transforming an existing mesh (rotate/translate) is just a matter of changing its associated transform matrix, which is reuploaded to the GPU on each draw call anyway

Well not in gideros: lua is rather slow and modifying vertices means reuploading them to GPU. On the other hand gideros rendering pipeline is very close to the GPU, and transforming an existing mesh (rotate/translate) is just a matter of changing its associated transform matrix, which is reuploaded to the GPU on each draw call anyway